public class e4_10{
 public static void main(String args[]){
  Lader.下底=100;
  Lader laderone = new Lader();
  Lader ladertwo = new Lader();
  laderone.设置上底(28);
  ladertwo.设置上底(66);
System.out.println("laderone的上底:"+laderone. 获取上底());
System.out.println("laderone的下底:"+laderone. 获取下底());
System.out.println("ladertwo的上底:"+ladertwo. 获取上底());
System.out.println("ladertwo的下底:"+ladertwo. 获取下底());
}
}
